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61.
Solitary intestinal fibromatosis (SIF) is very rare; only 9 cases have been described. A new case presenting unusually in a newborn is described and the previously reported cases are reviewed. SIF should be considered in the differential diagnosis of a newborn presenting with an intestinal perforation.  相似文献   
62.
Choriocarcinoma arising in the placenta, or intraplacental choriocarcinoma, has seldom been reported, particularly in the absence of maternal metastases. Reluctance to diagnose choriocarcinoma in the presence of chorionic villi can delay diagnosis; however, timely diagnosis of choriocarcinoma is prognostically important, both for the mother and infant. We report the clinicopathologic findings in five mothers and infants in whom choriocarcinoma was identified in the placenta. None of the mothers had a history of gestational trophoblastic disease in previous pregnancies. Three placentas were similar with a single small lesion grossly suggesting a small infarct; microscopically these consisted of infarcted areas surrounded by choriocarcinoma. These three mothers were unusual in that none had metastatic choriocarcinoma; two were treated with chemotherapy and remained disease-free; the third was lost to follow-up shortly following delivery. The remaining two mothers had known pulmonary metastases at time of delivery. One of these latter two placentas contained a large marginal lesion microscopically identified as choriocarcinoma. The fifth placenta had rare microscopic foci of choriocarcinoma, and sheets of necrotic choriocarcinoma were identified in “blood clot” submitted with the placenta. In four of the five cases the choriocarcinoma appeared to be arising from otherwise normal chorionic villi, and in no case was there invasion of the villous stroma. All of the infants survived, and none had evidence of choriocarcinoma. These cases support the concept that choriocarcinoma associated with otherwise normal pregnancy arises in the placenta and may be more common than reported. Received August 11, 1997; accepted December 8, 1997.  相似文献   
63.
McKeown-Eyssen (Cancer Epidemiol. Biomarkers Prevent., 3, 687-695, 1994) and Giovannucci (Cancer Causes Control, 6, 164-179, 1995), noting the striking similarity in lifestyle risk factors for colorectal cancer and insulin resistance, proposed that the hyperinsulinemia, glycemia and hypertriglyceridemia associated with insulin resistance promotes colon cancer. To compare the effect of diet on colon cancer promotion and insulin resistance in the F344 rat, we assessed the effect of fat, n-3 fatty acids and energy in pairwise comparisons on average size of aberrant crypt foci (ACF) and on glucose intolerance in the same animals in a single experiment. Diets high in fat and energy increased and diets with increased n-3 fatty acids and calorie restriction decreased both ACF growth and glucose intolerance compared with control diets. The measures of promotion of colon cancer and insulin resistance were strongly correlated (n = 98, r = 0.67, P < 0.001). In addition, both were highly correlated with daily energy intake (r = 0.62 and 0.66) and were also correlated with basal (post-prandial) insulin, glucose and triglycerides (r = 0.31-0.53, P < 0.01). We concluded that ACF growth and glucose intolerance are correlated for a wide range of diets and that increased circulating energy (glucose and triglycerides) may lead to both colon cancer promotion and insulin resistance.   相似文献   
64.
Colonoscopy is an integral part of the clinician armamentarium in the diagnosis of colorectal cancer and its precursor, the adenoma. Polypoid lesions when identified can be excised at colonoscopy and in turn reduce the risk of colorectal cancer. We prospectively evaluated the yield of colorectal cancer and adenomatous polyps by indication for colonoscopy over a one-year period. A total of 375 colonoscopies were carried out. The more common indications of colonoscopy were rectal bleeding, abdominal pain, surveillance of colorectal cancer and altered bowel habit. The highest yield for cancer was for rectal bleeding with 12.5% while surveillance of patients with a history of polyps yielded the highest percentage of new polyps. We conclude that rectal bleeding as an indication for colonoscopy yielded the highest number of cancers.  相似文献   
65.
目的在β-受体激动情况下,研究多非替利衍生物CPU 228对电刺激触发心肌细胞的胞浆Ca2+浓度([Ca2+]i)变化及钙瞬变动力学参数的影响.方法游离单个大鼠心室肌细胞,Fluo-3/AM负载,电刺激诱发心室肌细胞钙瞬变,定量测定心室肌细胞内Ca2+浓度变化,异丙肾上腺素(isoproterenol, ISO)100nmol·L-1激动β-受体,观察CPU 228 1 μmol·L-1对钙瞬变动力学参数、[Ca2+]i及钙负荷水平的影响.结果CPU 228 1 μmol·L-1对大鼠心室肌细胞[Ca2+]i的影响不明显(P>0.05);ISO 100 nmol·L-1显著升高大鼠心室肌细胞[Ca2+]i和细胞内钙负荷水平,缩短钙瞬变时程,并且增加钙瞬变的消除速率.CPU 228 1 μmol·L-1显著抑制ISO的上述作用.结论在β-受体激动情况下,CPU 228可以降低心肌细胞[Ca2+]i,使ISO改变的钙瞬变动力学参数恢复到正常水平.  相似文献   
66.
PURPOSE: To evaluate retrospectively the ability of an artificial neural network (ANN) to predict bladder cancer recurrence within 6 months of diagnosis and stage progression in patients with Ta/T1 bladder cancer, and 12-month cancer-specific survival in patients with T2-T4 bladder cancer. MATERIALS AND METHODS: Data were analyzed using a NeuralWorks Professional II/Plus software package. The input neural data consisted of clinicopathological and molecular characteristics. Distinct patient groups were used for the prediction of stage progression and tumor recurrence in Ta/T1 bladder cancers, and 12-month cancer-specific survival for patients with T2-T4 tumors. ANN predictions were compared with those of four consultant urologists. RESULTS: The accuracy of the neural network in predicting stage progression and recurrence within 6 months for Ta/T1 tumors and 12-month cancer-specific survival for T2-T4 cancers was 80%, 75% and 82% respectively; with corresponding figures for clinicians being 74%, 79% and 65%. On restricting the validation subset to patients with T1G3 tumors in relation to stage progression, the sensitivity of the ANN analysis increased to 100% with a specificity of 78% and an overall accuracy of 82%. The performance of the ANN in predicting stage progression in T1G3 tumors was significantly higher than that of clinicians (p = 0.25 for the ANN and p = 0.008 for clinicians, McNemar test). CONCLUSIONS: Data analysis using an ANN has been shown to be a useful adjunct in predicting outcomes in patients with bladder cancer and out-performs clinicians' predictions of stage progression in the high risk group of patients with T1G3 disease.  相似文献   
67.
目的:探讨乌贼墨对脾细胞和巨噬细胞NO生成及IFN-γ分泌的影响。方法:用Griess法和ELISA法分别检测了经乌贼墨灌胃处理后小鼠脾细胞和腹腔巨噬细胞培养上清中NO和IFN-γ的水平的变化。结果:乌贼墨灌胃处理小鼠后的第4、6天脾细胞及腹腔巨噬细胞(Mφ)可产生较高水平的NO;脾细胞可产生较高水平的IFN-γ,并且小鼠脾细胞NO的产生水平与IFN-γ产生水平呈正相关(r=0.98);用LPS和L-NMMA(NO抑制剂)分别同乌贼墨灌胃第6d小鼠的脾细胞一起培养,结果显示LPS可协同IFN-γ促NO水平升高。L-NMMA可抑制小鼠脾细胞的NO生成。结论:乌贼墨可促进巨噬细胞NO生成;脾细胞NO的产生与IFN-γ分泌水平呈正相关。  相似文献   
68.
食品级番茄红素对小鼠的免疫调节功能   总被引:4,自引:0,他引:4  
目的研究番茄红素对免疫系统的调节作用。方法实验小鼠随机分成3组:对照组、低剂量组(10mg/kg)、高剂量组(20mg/kg)。低剂量组、高剂量组分别用色拉油稀释的番茄红素灌胃,对照组用色拉油灌胃。30天后检测小鼠的脾淋巴细胞增殖程度、NK细胞的杀伤活性、迟发性变态反应的程度、巨噬细胞吞噬功能。结果与对照组比较,高剂量组能显著增强脾淋巴细胞的增殖能力,提高自然杀伤细胞的活性和巨噬细胞吞噬功能,增强小鼠的足跖肿胀度(P〈0.05)。除增殖反应外,低剂量组其他指标与对照组比较,差异均无显著性。结论番茄红素具有增强小鼠免疫调节的功能。  相似文献   
69.
目的:探讨4种口服给药方案治疗良性前列腺增生(BPH)所产生的成本-效果比.方法:选择我院门诊轻中度良性前列腺增生患者168例,随机分为4组,分别给予非那雄胺(A纽)、坦索罗辛(B组)、坦索罗辛多沙唑嗪加非那雄胺(C组)、普适泰(D组),运用药物经济学方法进行分析.结果:在成本相当的前提下,C组方案有效率最高.结论:坦索罗辛多沙唑嗪 非那雄胺治疗BPH不仅疗效好,可降低患者需要手术的危险性,而且可降低急性尿潴留发生率.  相似文献   
70.
目的 探讨宫颈癌皮肤转移患者的临床特点、诊治过程及预后。方法 我院自2006年6月至2011年6月共收治宫颈癌患者574例,其中5例确诊为宫颈癌皮肤转移。收集该5例患者的临床、病理及随访资料,并分析其临床特点、诊治过程及预后。结果 宫颈癌皮肤转移的发生率为0.87%(5/574),均为宫颈癌ⅡA~ⅢB期患者。其中,4例在确诊宫颈癌并完成治疗后的随访过程中发现皮肤转移; 1例为初治患者,入院后1个月发现逐渐增大的皮肤结节,手术切除后确诊为皮肤转移。4例患者合并肺部、骨骼等其他部位的转移。4例患者行手术完整切除皮肤病灶,术后1例因合并有多发骨转移且骨痛明显接受核素治疗,1例行全身化疗,2例仅接受对症支持治疗。1例患者因头皮转移病灶向内侵犯颅骨,无法行手术切除,行穿刺检查诊断转移后接受调强适形放疗。随访中3例患者死亡,另2例诊断宫颈癌皮肤转移分别为3个月、5个月,仍存活。结论 宫颈癌皮肤转移发生率低,通常合并有其他脏器的转移,治疗较困难,预后较差。  相似文献   
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